Computer Networks 1 - Dec 2015

Computer Science Engg. (Semester 5)

TOTAL MARKS: 100
TOTAL TIME: 3 HOURS (1) Question 1 is compulsory.
(2) Attempt any four from the remaining questions.
(3) Assume data wherever required.
(4) Figures to the right indicate full marks. 1 (a) Define network. With a neat diagram, explain the four basic topologies.(5 marks) 1 (b) With the help of a diagram, explain the functionalities of each layer of OSI reference model.(10 marks) 1 (c) List and explain the four levels of addresses used in an internet employing the TCP/IP protocols.(5 marks) 2 (a) Define latency. Briefly explain the components of latency. What are the propagation time and transmission time for a 5 MByte message (image), H the bandwidth of the network is 1 Mbps? Assume that the distance between the sender and receiver is 12000 km and that light travels at 2.4×10⁸ m/s.(8 marks) 2 (c) What is line coding? Represent the sequence '01001110' using NRZ-L, NRZ-I and Manchester schemes.(4 marks) 3 (a) What is TDM? Explain in detail.(7 marks) 3 (b) Explain virtual circuit network with an example, and also briefly discuss the phases.(10 marks) 3 (c) Five channels, each with a 100 kHz bandwidth are to be multiplexed together. What is the minimum bandwidth of the link is there is a need for a guard band of 10 kHz between the channels to prevent interference?(3 marks) 4 (a) How does datawords and codewords is represented in block coding and also explain how can errors be selected and corrected by using block coding.(10 marks) 4 (b) Find the code word using CRC given data ?1101? and generator ?1100?.(10 marks) 5 (a) With a neat diagram, explain any two protocols of noisy channel.(12 marks) 5 (b) Explain the frame format of HDLC protocol.(8 marks) 6 (a) Describe pure ALOHA and slotted ALOHA.(10 marks) 6 (b) What is channelization? List and explain the channelization protocols.(10 marks) 7 (a) Explain the different types of addressing mechanism in IEEE 802.11.(5 marks) 7 (b) Define Bluetooth and explain the architecture of Bluetooth.(5 marks) 7 (c) With a neat diagram, explain the categories of connecting devices.(10 marks) 8 (a) Explain classful addressing and classless addressing with respect to IPV4.(8 marks) 8 (b) Explain in detail IPV6 packet format.(8 marks) 8 (c) Give a comparison between IPV4 and IPV6.(4 marks)